widget/windows/nsNativeDragSource.cpp

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #include "nsNativeDragSource.h"
   7 #include <stdio.h>
   8 #include "nsISupportsImpl.h"
   9 #include "nsString.h"
  10 #include "nsIServiceManager.h"
  11 #include "nsToolkit.h"
  12 #include "nsWidgetsCID.h"
  13 #include "nsIDragService.h"
  14
  15 /*
  16  * class nsNativeDragSource
  17  */
  18 nsNativeDragSource::nsNativeDragSource(nsIDOMDataTransfer* aDataTransfer) :
  19   m_cRef(0),
  20   m_hCursor(nullptr),
  21   mUserCancelled(false)
  22 {
  23   mDataTransfer = do_QueryInterface(aDataTransfer);
  24 }
  25
  26 nsNativeDragSource::~nsNativeDragSource()
  27 {
  28 }
  29
  30 STDMETHODIMP
  31 nsNativeDragSource::QueryInterface(REFIID riid, void** ppv)
  32 {
  33   *ppv=nullptr;
  34
  35   if (IID_IUnknown==riid || IID_IDropSource==riid)
  36     *ppv=this;
  37
  38   if (nullptr!=*ppv) {
  39     ((LPUNKNOWN)*ppv)->AddRef();
  40     return S_OK;
  41   }
  42
  43   return E_NOINTERFACE;
  44 }
  45
  46 STDMETHODIMP_(ULONG)
  47 nsNativeDragSource::AddRef(void)
  48 {
  49   ++m_cRef;
  50   NS_LOG_ADDREF(this, m_cRef, "nsNativeDragSource", sizeof(*this));
  51   return m_cRef;
  52 }
  53
  54 STDMETHODIMP_(ULONG)
  55 nsNativeDragSource::Release(void)
  56 {
  57   --m_cRef;
  58   NS_LOG_RELEASE(this, m_cRef, "nsNativeDragSource");
  59   if (0 != m_cRef)
  60     return m_cRef;
  61
  62   delete this;
  63   return 0;
  64 }
  65
  66 STDMETHODIMP
  67 nsNativeDragSource::QueryContinueDrag(BOOL fEsc, DWORD grfKeyState)
  68 {
  69   static NS_DEFINE_IID(kCDragServiceCID,  NS_DRAGSERVICE_CID);
  70
  71   nsCOMPtr<nsIDragService> dragService = do_GetService(kCDragServiceCID);
  72   if (dragService) {
  73     DWORD pos = ::GetMessagePos();
  74     dragService->DragMoved(GET_X_LPARAM(pos), GET_Y_LPARAM(pos));
  75   }
  76
  77   if (fEsc) {
  78     mUserCancelled = true;
  79     return DRAGDROP_S_CANCEL;
  80   }
  81
  82   if (!(grfKeyState & MK_LBUTTON) || (grfKeyState & MK_RBUTTON))
  83     return DRAGDROP_S_DROP;
  84
  85   return S_OK;
  86 }
  87
  88 STDMETHODIMP
  89 nsNativeDragSource::GiveFeedback(DWORD dwEffect)
  90 {
  91   // For drags involving tabs, we do some custom work with cursors.
  92   if (mDataTransfer) {
  93     nsAutoString cursor;
  94     mDataTransfer->GetMozCursor(cursor);
  95     if (cursor.EqualsLiteral("default")) {
  96       m_hCursor = ::LoadCursor(0, IDC_ARROW);
  97     } else {
  98       m_hCursor =  nullptr;
  99     }
 100   }
 101
 102   if (m_hCursor) {
 103     ::SetCursor(m_hCursor);
 104     return S_OK;
 105   }
 106
 107   // Let the system choose which cursor to apply.
 108   return DRAGDROP_S_USEDEFAULTCURSORS;
 109 }